Two cases of the caudal duplication anomaly including a discordant monozygotic twin.

We present two unrelated patients with various duplications in the caudal region. One patient presented with a duplication of the distal spine from L4, left double ureter, duplication of the vagina and cervix, and duplication of the distal colon. The second patient was diagnosed with a duplication of the colon, bladder, vagina and uterus. The first patient had an unaffected monozygotic twin sister. Dominguez et al. [1993: Am J Dis Child 147:1048-1052] presented six similar cases, and introduced the name "caudal duplication syndrome." The pathogenesis of the caudal duplication anomaly is unclear. The possibility of a polytopic primary developmental field defect or a disruptive sequence are discussed. On the other hand, somatic or germline mutations in certain developmental genes could be involved, as illustrated by the mouse mutations disorganisation and fused. DNA-analysis of the AXIN1 gene, the human homologue of the gene responsible for fused, performed in our first patient, did not show any apparent pathogenic mutation.

Aerodynamic properties of the low-resistance Groningen button.

Shunt tracheoesophageal speech is currently the most successful form of voice and speech rehabilitation in laryngectomees. Insertion of valve prostheses into the tracheoesophageal shunts has overcome drawbacks caused by stenosis of the shunt and aspiration. In 10 years of satisfactory results with the standard Groningen button valve prosthesis, the overall concept of this device has proved its value. The airflow resistance, however, is relatively high, so that a low-resistance device has been developed without changing the favorable characteristics of the standard device. The design of this low-resistance Groningen button is described. The airflow resistances of the standard and low-resistance Groningen buttons have been measured and compared. The airflow resistance of the low-resistance Groningen button is also compared with the reported airflow resistances of various other valve prostheses.

Scrotal hematoma, anemia, and jaundice as manifestations of adrenal neuroblastoma in a newborn.

Clinically, a neuroblastoma presents mostly as an abdominal mass. Within the tumor, bleeding can be present, sometimes extending in to its surroundings. This case report describes a neuroblastoma, presenting as scrotal hematoma in a newborn boy, which initially raised the suspicion of a torsion testis. In this patient, the bleeding descended through the subcutaneous and muscular tissue into the scrotum. In addition, anemia and jaundice were marked features. This clinical manifestation of a neuroblastoma has not been reported previously. Ultrasonography is advised as the first diagnostic step to exclude retroperitoneal origin of the bleeding. Magnetic resonance imaging and meta-iodobenzyl guanidine scanning were helpful tools in the final diagnostic workup.

The microvascular architecture of the scalp in the human fetus at term. Implications for measuring blood gases and flow rate.

A microscopic study is presented on the depth distribution of the microvessels in the scalp of two human fetuses at term. The basal membrane showed a smooth line without papillary structures resulting in a thin epidermal layer of 25 microns. The distance from the scalp surface to the periosteum appeared to be almost 1.8 mm. The capillary density showed a peak of approximately 1.2 capillary cross-sections per 10(4) microns 2 in the first 200 microns of the dermis. In the middle of the dermis the capillary density fell to 0.2 cross-sections per 10(4) microns 2 to rise again in the lower part of the dermis to 1.6 cross-sections per 10(4) microns 2, which remained the approximate count in the subcutaneous tissue. The arterioles and venules showed significant numbers in the lower part of the dermis and were virtually absent in the subcutis. Of all 4570 microvessel cross-sections that were studied in a tissue volume of 0.6 mm3, not a single one showed the features of an arteriovenous anastomosis. The possible implications for laser Doppler flowmetry and continuous blood gas measurement of the fetal scalp are discussed.

Clinical experience with the low-resistance Groningen button.

Since its introduction in 1980, the standard Groningen button prosthesis has been of proven value for post-laryngectomy voice rehabilitation. Its relatively high airflow resistance has, however, been the cause of failure in achieving good post-laryngectomy tracheoesophageal shunt speech in some patients. The low-resistance Groningen button (LRGB) was therefore designed, thus reducing airflow resistance by 50% when compared to the standard device. The clinical performance of the LRGB, and the effect of prophylactic amphotericin, was assessed in 32 patients. The device lifetime, intratracheal phonatory pressures and patients' subjective acceptances of the prosthesis were recorded. Present findings showed that the majority of the patients preferred the LRGB as it required less effort to operate than the standard device. The intra-tracheal phonatory pressure was found to increase with time, but this change was prevented with the prophylactic use of amphotericin to inhibit concurrent colonization by Candida spp, which also helped to prolong the prosthesis lifetime.